Running script file through subprocess

Question

I'm attempting to run a Linux script through Python's subprocess module. Below is the subprocess command:

result = subprocess.run(['/dir/scripts/0_texts.sh'], shell=True)
print(result)

Here is the 0_texts.sh script file:

cd /dir/TXTs

pylanguagetool text_0.txt > comments_0.txt

The subprocess command executes the script file, writing a new comments_0.txt in the correct directory. However, there's an error in the execution. The comments_0.txt contains an error of "input file is required", and the subprocess result returns returncode=2 . When I run the pylanguagetool text_0.txt > comments_0.txt directly in the terminal the command executes properly, with the comments_0.txt written with the proper input file of text_0.txt .

Any suggestions on what I'm missing?

Answer 1

There is some ambiguity here in that it's not obvious which shell is run each time 0_texts.sh is invoked, and whether it has the values you expect of environment variables like PATH , which could result in a different copy of pylanguagetool running from when you call it at the command line.

First I'd suggest removing the shell=True option in subprocess.run , which is only involving another, potentially different shell here. Next I would change subprocess.run(['/dir/scripts/0_texts.sh']) to subprocess.run(['bash', '/dir/scripts/0_texts.sh']) (or whichever shell you wanted to run, probably bash or dash ) to remove that source of ambiguity. Finally, you can try using type pylanguagetool in the script, invoking pylanguagetool with its full path, or calling bash /dir/scripts/0_texts.sh from your terminal to debug the situation further.

A bigger-picture issue is, pyLanguageTool is a Python library, so you're almost certainly going to be better off calling its functions from your original Python script directly instead of using a shell script as an intermediary.